The Good Harbor Bay Trail is mostly flat flat with a few small slopes. A short section of low coastal dunes near the beginning of the trail provides access to the beach. Then the trail turns away from Lake Michigan and is in the woods for the remainder of its length. One section passes through swamp, and small foot bridges help you cross some wet spots. Check out MichiganTrailMaps.com for more trail info and a detailed map.
A Park Pass is required for all trail use within the Sleeping Bear Dunes National Lakeshore: Fee Information.